Question 1mediummultiple choice
Full question →- → Why each wrong option is wrong in this specific scenario
- → When each wrong option would be correct
- → Real-world analogy and exam trap analysis
- → Related glossary terms and similar practice questions
Question 1,475 of 1,052
mediummultiple choiceObjective-mapped
CCNA Practice Question: A network technician is troubleshooting a…
This 200-301 practice question tests your understanding of 200-301 exam topics. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A network technician is troubleshooting a connectivity issue where a user's email client cannot send messages, but the client can receive emails. The technician uses a protocol analyzer and sees that the client is successfully resolving the mail server's domain name to an IP address and establishing a TCP connection, but the server responds with an application-layer error. At which layers of the OSI model are the problem and the successful operations occurring, respectively?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The problem is at the Application layer (Layer 7); successful operations are at the Application layer (Layer 7) and Transport layer (Layer 4).
The successful DNS resolution occurs at the Application layer (Layer 7) because DNS is an application protocol. The TCP connection establishment happens at the Transport layer (Layer 4). The email sending failure is also an Application layer issue because the error is generated by the mail server's application (e.g., SMTP authentication failure or mailbox quota exceeded). Thus, the problem is at Layer 7, while successful operations are at Layers 7 and 4.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The problem is at the Transport layer (Layer 4); successful operations are at the Application layer (Layer 7) only.
Why it's wrong here
This is incorrect because the TCP connection was successfully established, indicating no Transport layer problem. The error is an application-layer response.
- ✓
The problem is at the Application layer (Layer 7); successful operations are at the Application layer (Layer 7) and Transport layer (Layer 4).
- ✗
The problem is at the Network layer (Layer 3); successful operations are at the Data Link layer (Layer 2) and Physical layer (Layer 1).
Why it's wrong here
This is incorrect because the technician observed TCP connection establishment, which requires Network layer IP routing to be functional. The problem is not at Layer 3.
- ✗
The problem is at the Presentation layer (Layer 6); successful operations are at the Session layer (Layer 5) and Transport layer (Layer 4).
Why it's wrong here
This is incorrect because the error is an application-layer response, not a data format or encryption issue (Presentation) or session management issue (Session).
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The 200-301 exam frequently reuses these exact scenarios with slightly different constraints.
✓The problem is at the Application layer (Layer 7); successful operations are at the Application layer (Layer 7) and Transport layer (Layer 4).Correct answer▾
Why this is correct
DNS resolution (Layer 7) and TCP connection (Layer 4) are successful. The sending error is an Application layer issue, as the mail server returns an application-level error.
✗The problem is at the Transport layer (Layer 4); successful operations are at the Application layer (Layer 7) only.Wrong answer — click to see why▾
Why this is wrong here
The TCP handshake succeeded, so the Transport layer is working. The error message is generated by the application, not the transport protocol.
✗The problem is at the Network layer (Layer 3); successful operations are at the Data Link layer (Layer 2) and Physical layer (Layer 1).Wrong answer — click to see why▾
Why this is wrong here
Successful TCP connection implies IP routing (Layer 3) is working. The error is not related to addressing or routing.
✗The problem is at the Presentation layer (Layer 6); successful operations are at the Session layer (Layer 5) and Transport layer (Layer 4).Wrong answer — click to see why▾
Why this is wrong here
Email sending failures are typically application logic errors, not encryption/formatting or session problems. Also, DNS is an Application layer protocol, not Session or Presentation.
Analysis generated from the official 200-301blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
- Use explanations to understand the rule behind the answer.
TExam Day Tips
- Underline the problem statement mentally.
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the 200-301 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Got this wrong? Here's your next step.
Identify which 200-301 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Related practice questions
Related 200-301 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
CCNA subnetting practice questions
Practise IPv4 subnetting, CIDR, masks, host ranges and subnet selection.
CCNA OSPF practice questions
Practise OSPF neighbours, router IDs, metrics, areas and routing-table interpretation.
CCNA VLAN practice questions
Practise VLANs, access ports, trunks, allowed VLANs and switching scenarios.
CCNA STP practice questions
Practise spanning tree, root bridge election, port roles and STP troubleshooting.
CCNA EtherChannel practice questions
Practise LACP, PAgP, port-channel behaviour and bundle requirements.
CCNA ACL practice questions
Practise standard and extended ACLs, permit/deny logic and traffic filtering.
CCNA NAT practice questions
Practise static NAT, dynamic NAT, PAT and inside/outside address translation.
CCNA DHCP practice questions
Practise DHCP scopes, relay, leases and troubleshooting.
CCNA show ip route practice questions
Practise routing-table output, longest-prefix match, AD and route selection.
CCNA show interfaces trunk practice questions
Practise trunk verification and VLAN forwarding across switches.
CCNA wireless security practice questions
Practise WLAN security, authentication and wireless architecture concepts.
CCNA IPv6 practice questions
Practise IPv6 addressing, routes, neighbour discovery and common IPv6 exam traps.
Practice this exam
Start a free 200-301 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this 200-301 question test?
Read the scenario before looking for a memorised answer.
What is the correct answer to this question?
The correct answer is: The problem is at the Application layer (Layer 7); successful operations are at the Application layer (Layer 7) and Transport layer (Layer 4). — The successful DNS resolution occurs at the Application layer (Layer 7) because DNS is an application protocol. The TCP connection establishment happens at the Transport layer (Layer 4). The email sending failure is also an Application layer issue because the error is generated by the mail server's application (e.g., SMTP authentication failure or mailbox quota exceeded). Thus, the problem is at Layer 7, while successful operations are at Layers 7 and 4.
What should I do if I get this 200-301 question wrong?
Identify which 200-301 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Keep practising
More 200-301 practice questions
- A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that w…
- A switch has DHCP snooping enabled, but users still experience IP-to-MAC spoofing attacks. Which additional feature shou…
- Switch SW1 sends traffic for VLAN 30 across a trunk to SW2, but hosts in VLAN 30 on SW2 cannot communicate with hosts in…
- What problem is HSRP designed to solve?
- Which DHCP message does the client send to formally accept an offered address?
- What metric does RIP use to choose the best path?
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Loading comments…
Sign in to join the discussion.
This 200-301 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-301 exam.